Abstract: The invention relates to a cooling device (100) for a rotatable anode (10) which is used for producing X-rays in an X-ray tube comprising a focal path (11), on which an electron stream is projected, and supporting elements (15). In order to efficiently cool the rotatable anode, a liquid (13) is located between the focal path (11) and the supporting elements (15), said supporting elements (15) simultaneously form condensation surfaces (16) and a vaporisation surface is formed on the focal path (11), the liquid is evaporated on the evaporation surface (19) and appears on the condensation surfaces (16) in the form of a vapour (18), wherein it is condensed for returning to the focal path (11) in the form of a condensate (22) by the action of centrifugal forces applied on the rotatable anode (10).